Community Assembly, Migration And Biodiversity At Multiple Spatial Scales: A Case Study Of The Carboniferous Fossil Record Using Brachiopods Of The Ozark Dome, USA And The Paleobiology Database, With Implications For Invasive Species And Conservation Biology

Grantee Research Project Results

Community Assembly, Migration And Biodiversity At Multiple Spatial Scales: A Case Study Of The Carboniferous Fossil Record Using Brachiopods Of The Ozark Dome, USA And The Paleobiology Database, With Implications For Invasive Species And Conservation Biology

Description:

Objective:

Carboniferous age brachiopod fossils are the subjects of this study. Data will be collected from the Ozark Mountains of Arkansas and Oklahoma to understand the details of how biodiversity is partitioned within a single region. Carboniferous brachiopod data from the Paleobiology Database (PBDB; www.paleodb.org Exit ) will be used to analyze biodiversity at continental and global spatial scales.

The second aspect of this research project will explore the interactions between species migration and biodiversity. First, a null biogeographic model of species migration and biodiversity will be created to provide a hypothesis to test against real data. The PBDB will be used to generate Carboniferous brachiopod data sets, from which migration patterns can be analyzed in light of global climate change as the Earth transitioned from a greenhouse world to icehouse world.

The objective of this research is to assess the roles of spatial scale and migration in maintaining biodiversity in Carboniferous age brachiopods over geologic time scales. Understanding the long-term mechanisms of biodiversity dynamics are essential for addressing, and hopefully reversing, the current biodiversity crisis.

Approach:

Field data will be collected using a spatio-temporal hierarchy with five levels (collection, bed, outcrop, depositional environment, depositional sequence). The final data matrix will have at least 243 individual collections. The resulting data matrix will then be used to analyze biodiversity patterns within the Carboniferous Period of the southern Ozark Dome. Simple richness and Simpson’s l will be calculated at each of the five levels of the hierarchy and diversity will be partitioned additively among the levels.

Carboniferous brachiopod biodiversity will also be analyzed at the global scale using the PBDB. The advantage of using the PBDB over the field data is that it provides species richness information on a global scale. Thus, a similar hierarchical analysis can be applied to global data, which can't be done for the detailed field collections from a single region.

The status of migration as an evolutionary process, such as origination and extinction, will be explored through the development of a null model. The null numerical model will explore how changing migration probabilities for species interact with regional and global diversity in a situation where origination and extinction are equal. The results of the model will then be used as a null hypothesis to test against actual data, which will be culled from the PBDB, again for Carboniferous brachiopods.

Expected Results:

If the goal of conservation biology is to preserve biodiversity in perpetuity, it is necessary to understand biodiversity dynamics for periods of time much longer than are available from studying modern ecosystems alone. The results of this study will shed light on how biodiversity is partitioned in space over geologic time scales. This will be invaluable to conservation biologists who are charged with the task of selecting ecological preserves. With knowledge of the minimum spatial scale required to preserve maximum diversity over millennia, preserves can be created that preserve areas that are of adequate size and environmental heterogeneity.

The results of the migration analyses will be applicable to understanding the effects of climate change as well as invasive species on biodiversity. As global warming proceeds in our own era, barriers to species migration will be altered. The results of this study will shed light on how diversity changes as previously isolated species are allowed to mix or as populations of single or multiple species are isolated from one another. This sort of information can also be applied to the management of invasive species. Indeed, invasive species are simply species whose ability to migrate across regions or continents is enhanced through anthropogenic activities.

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.